Metal oxides can be widely applied to transparent electrodes, light-emitting diodes, solar cells, gas sensors, as well as the field of displays. In various application fields of metal oxides, the metal oxides are usually required to possess certain electrical characteristics, and the main electrical characteristic parameters comprise carrier concentration, contact resistance, electrical resistivity or the like.
In order to achieve ohmic contact of metal oxides prepared under different conditions, argon plasma, hydrogen plasma or N2O plasma can be utilized to perform treatments on the metal oxides so as to improve the ohmic contact of the metal oxides. However, the metal oxides after the above-described plasma treatments do not present good ohmic contact. FIG. 1 is an I-V characteristic spectral line of a metal oxide in the prior art. As shown in FIG. 1, the I-V characteristic spectral line of the metal oxide in the prior art is a curve, indicating that there exists a schottky barrier at the position where the surface of the metal oxide comes into contact with an electrode of metal indium, metal molybdenum or a transparent electrode of indium-tin oxide (ITO) or the like. Therefore, if the metal oxide is formed into a device, the contact resistance between the metal oxide and the electrodes is large, resulting in a relatively high power consumption.